Stay bolt



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y "r. s. WHEELWRIGHT STAY BOLT F'ile d Nov. 15. 1930 v l I I I I IIllllllllllll IIl-Illlllllllllllll Patented :July 19, 1932 unITansTA-TEsPATENT mm:-

' THOIASB. WHEEIQWBIGHT, OF RICHMOND, VIRGINIA, ASSIGNOB TO OLD DOMINIONmen a mm. woaxs,

OI BELLE ISLE, RICHMOND, VIRGINIA, A GORPQBATION OI" BTAY BOLTIndication fled November 15, 1930. Serial No. 495,994.

This invention "relates to flexible hollow I staybolts for locomotiveand other boilers which are subjected to excessive vibration, andparticularly to that type of flexible staybolt which is provided with arounded head,

at one end, for flexible connection with the outer shell of the boilerand a tell-tale hole extending thro'u bout the entire length.

staybolts of t e present type are usually manufactured from stock whichhas been severely tested to make sure that it conforms to very exactingspecifications. However,

as it has been customary to form the headof the bolt by a methodre uirinexcessive heating of the stock, and orm t e tell-tale hole by drillingsaid stock, longitudinally, the nature of themetal is necessarilychanged and injured to. such an extent that the value of the inspectionunder specifications is wholly lost.

In view of the foregoing, itis an object of the present invention toproduce a flem'ble tell-tale staybolt, of the headed type, wherein thestock has been provided with the telltale hole prior to the time oftesting the same, and a further object to produce a bolt where,-

in the heading of thesame isaccomplished without subjecting the originalstock to the heat required for forging the head.

In order to accomplish the first object mentioned, it is advisable toform the bolt of -hollow rolled staybolt stock such as is set forth inUnited States Patents No. 1,618,142

' the tell-tale hole is then protected from corbeing threaded thereon orby and Nb. 1,668,705. Another reason for using hollow rolled'stock isthat the wall of rosion by. the skin of the metal as well as by thesilica flour which is burned into the said wall during the process ofmanufacture.

' To accomplish the second object of the in vention, the head isattachedfo the-bolt by formed integral'therewith by swaging or ot erprocess not requiring the application of heat, as 7 more fully describedlater herein. i

A further object of the invention isto.

provide a staybolt of the typementioned wherein the tell-talehole willextend entirely through the cap usually provided at the outer ends ofsuch bolts, so that it possible taken in connection with to inspect thesame by inserting a testing instrument into the tell-tale hole withoutremoving the said cap.

Other objects and advantages will be ap-' parent from the followingdescription when the accompanying drawing. r

In the drawingi I Figure 1 is asectional view showing one form of theinvention.

Figure 2 is a sectional view showing another form of the invention.

Figure 3 is a fragmentary sectional view showin the device used forscrewin ,the form 0 bolt, of Figure 2, into the inner oiler sheet.

Figure 4 is a detail sectional view showing the bolt seated directly ina seat in the boiler sheet, the sleeve not being used.

1 Referring particularly to the accompanying drawing, and especlally toFigure 1, 10 represents a portion of the outer sheet of a steam boiler,while 11 represents a portion of the inner sheet thereof. In the outersheet '10 there is formed an opening 12, having a smooth wall, while inthe inner sheet 11, in direct alinement with the opening 12, is athreaded opening 13. Disposed within the opening 12, of the outer sheet,is a' sleeve 14,

said sleeve being welded to the outer face of the boiler sheet, as shownat 15. This sleeve projects inwardly, beyond the sheet, and also bolt,and its outer face, which is flat, is provided with wrench receivingnotches 19, whereby to permit screwing the bolt into the opening- 13.This manner of attachin the head to the bolt obviates the necessity ofeating the latter, resulting in danger to the tends slightly beyond theflat face of the head 18, and such projecting end is rounded, as

shown at 23, to bQ'I'GCGlVGd in a socket 2 1, formed in the inner end ofa stem 25. The.

socket end of the stem is slightly larger, in diameter, than the majorportion thereof, whereby to provide a shoulder 25'. Theouter end\of thisstem projects through the opening 21, o f the cap 20.

Engaged on the stem 25 is a concavo;convex bearing washer or disk 26,preferably formed from brass, which bears against the umer concavesurface of the cap 20, and disposed within the concavity of said disk isa packing disk 27 preferably formed of lead, or other suitable softmetal, which is compressible,

- and which can be forced into the joint between the disk 26 and thestem 25, whereby to render said joint steam-tight. Also disposed on thestem 25, and disposed against the pack ing disk 27, is a hard metalwasher or bearing plate 28. Encircling the stem 25, and bearlngrespectively against the shoulder 25' and the plate 28, is a strong coilspring 29, which, when the arts are properly assembled, urges the dlsk26 tightly against the inner face 'of the cap.

Formed longitudinally throughout the entire length of the bolt is atelltale hole repre sented by the numeral 30, Wh10l1 is formed in thestock, from which the staybolt is made, and which is described in myprior patents, 1,618,142 and 1,668,705, as already stated herein. Thisobviates the necessity of boring the telltale hole after the stock hasbeen tested, for reasons already set forth,

Formed longitudinally and centrall through the stem 25 is an opening16', whic forms a continuation ofthe telltale hole 30,

of the staybolt, the inner end of said opening 16 registering with theadjacent end of said telltale hole, as clearly seen in Figure 1 In theform of the device shown in Figure 2, the head 31, of the staybolt 32,is formed integrally therewith. This may be done by swaging the metalinto a suitable form,.with the use'of a swaging tool which will, at thesame time, produce the conical socket 33. In this form, also, the stem34 is provided. with a rounded head 35, at its inner end, which rests insaid conical socket 33. To provide for screwing this bolt into thethreaded opening of the inner sheet of the boiler, a threaded recess 36is formed at the bottom of the socket 33, to receive the threaded stem37 of a conical may be used without the sleeve, by positioning the headof the bolt directly on a seat 40, formed in the opening 41, on theboiler sheet, as shown in Figure 4. When this arrangement is used, thecap 20 may be welded directly to the boiler sheet.

What is claimedis:

1. In a staybolt structure, a casing comprising a sleeve and cap havinouterand inner spherical seat surfaces, an said cap having an opening inits outer wall concentric with its seat surface, a bolt having an endportion disposed in said casing and provided with an inner head memberhaving a spherical seat surface pivotally engaging the seat surface ofthe "sleeve, an axial extension projecting beyondsaid. inner head memberand projecting outwardly through the opening in the cap, the bolt andits extension being provided with a tell-tale hole extending.continuously from. end to end thereof, an outer head member slidable onthe bolt extension toward and from the inner head member and having aspherical seat surface pivotally en gaging the seat surface of the cap,and resilient means acting to force the outer head, member outward andaway from the inner head member and against said seat surface of thecap.

2. In a staybolt structure, acasing comprising a sleeve and cap havingouter and inner spherical seat surfaces, and said cap havin an openingin its outer wall concentric wit its seat surface, a bolt having an endportion disposed in said casing and provided with an inner head member.having a spherical seat surface pivotally engaging the seat surface ofthe sleeve, an axial extension projecting beyond said inner head memberand projecting outwardly through the opening in the cap,

a tell-tale hole extending continuously from end to end thereof, anouter head member slidable onthe bolt extension toward and from theinner head member and having a spherical seat surface pivotally engagingthe seat sur face of the cap, a packing member for closing the jointbetween the bolt extension and outer head member, and a spring forpressmg the packing againstthe outer head member and acting to force theouter head member outward and away from the inner head member andagainst said seat surface of the cap.

3. A staybolt construction for use in connection with a boiler sheethaving a seat and a centrally apertured cap secured in position 1.05: Ithe bolt and its extension being provided with over saidseat,vcomprising a bolt having 11. head seated on said seat and providedwith a stem extending beyond said head into said cap and through theaperture thereof, a centrally apertured spring pressed bearing disk onthe stem having a face snugly and slidably contacting with a face ofsaid cap, a

packing against said disk, andmeans fo r pressing said packing into theaperture of said disk and against said stem.

4. A staybolt construction for use in connection With a boiler sheethaving a seat and a centrally apertured cap secured in position oversaid seat, comprising a bolt having a head seated on said seat andprovided with a stem extending beyond said head into said cap andthrough the aperture thereof, a centrally apertured spring pressedbearing disk on the stem having a face snugly and slidably contactingwlth a face of said cap, a packing against said disk, and means forpressing said packing into the aperture of said disk and against saidstem, said stem being movably engaged with said head.

In testimony whereof, I aflix my signature.

THOMAS S. WHEELWRIGHT.

